Modern two-way messaging systems employ frequency reuse for spectrally efficient communication with portable subscriber units. Correct estimation of how many and which subscriber units can simultaneously receive different messages from different base transmitters without undue interference is difficult. A prior art technique has been for the subscriber unit to measure the quality of a received color code corresponding to a base transmitter. Another prior art technique has been to estimate the location of the subscriber unit from received signal strength at the base receivers.
These prior art techniques have not always provided a reliable estimate of the optimum frequency reuse plan for communication with the subscriber unit. Quality of color code reception and subscriber unit location cannot always determine how many and which base transmitters are within range of the subscriber unit.
Thus, what is needed is a method and apparatus that can dynamically select a frequency reuse plan for communicating with a portable subscriber unit. Preferably, the selected frequency reuse plan should be closely related to how many and/or which transmitters are within range of the subscriber unit.